HIV transmission continues in high-drug-use urban neighborhoods despite prevention programs targeting drug injectors, other drug users, and their sex partners. New intervention modes are needed. A promising approach is community-level intervention to assist resident's "social control actions" and to re-shape social norms of drug users, their families, and their neighbors. Little is known, however, about how these variables affect HIV risk behaviors or "trailblazer behaviors" (that can sometimes be stepping-stones to risk behaviors) -- particularly in the context of widespread stressful life events that can increase the lure of high-risk behaviors. This project will study relationships between trailblazer and risk behavior, on the one hand, and, on the other, local area drug scenes, residents' actions to protect themselves and others, normative pressures, internalized norms and stressful life events. Eight hundred adults in a Brooklyn community with widespread drug use and HIV infection will be interviewed at baseline and one year later. We will recruit 100 household residents and 100 street/venue-recruited subjects in each of four types of "sub-neighborhoods": (a) A high-drug-use area where residents are quite active in social control action; (b) a high-drug-use area without visible social control action; (c) an area of low drug use but with visible social control action; and (d) an area of low drug use without visible social control action. Examples of each type have already been identified. We will (1) develop measures of social control actions and "street/decency" norms that may affect trailblazer and risk behaviors; (2) determine characteristics of those who get involved in social control actions, have protective norms, and engage in risk and trailblazer behaviors in each of these four local contexts; (3) study the extent to which, during the year between baseline and follow-up, residents undergo stressful life events, change their involvement in social-control activity, and change trailblazer and risk behaviors in each type of local area; (4) study how stressful life events, use of sociomedical agencies, "street/decency" codes, and family and peer norms are associated with changes in risk and trailblazer behaviors and social-control actions; and determine how local area "type" mediates these associations; and (5) develop, in coordination with community agencies and local area residents and "street people," new intervention approaches to apply in high-risk communities. Thus, this research will provide scientific underpinning to develop community interventions to reduce risk and trailblazer behaviors in localities characterized by different levels of drug use and of "indigenous" social control activities.